The purpose of the proposed research is to assess the long-term consequences of prenatal exposure to progesterone, norethisterone (an androgenic progestin), and prednisone (a synthetic corticosteroid) on human psychological/behavioral and physical development. Assessment of personality, temperament, cognitive abilities, school achievement and behavior, gender identity/role, mental health, social deviance, puberty, and physical growth and developmental milestones will be included. A unique sample of 237 subjects, members of a consecutive birth cohort of over 9000 born from 1959 to 1961 in Copenhagen, Denmark will be the focus of these evaluations. Prospective data, commencing prior to birth, are available on all cohort members so that control subjects can be matched on a broad spectrum of appropriate pregnancy, obstetric and birth complications, maternal disorders, perinatal factors, and family/social variables. A second comparison group will be composed of unexposed siblings. Additional data will be generated from the Danish Registries which compile information on admissions to psychiatric hospitals, social deviance, serious illness, and penal incarceration. School records, yearly school medical examinations and specialist reports are also available for analysis. The availability of these prospectively collected data in conjunction with our proposed contemporary evaluation provides the singular opportunity to study longitudinally the development of these hormone-exposed individuals from birth to adulthood while only expending the time and resources necessary for a cross-sectional investigation. Finally, parallel studies with laboratory animals will be conducted in order to evaluate experimentally the long-term effects of exposure to the three hormones on genital morphology, developmental milestones, reproductive physiology, longevity, aggression, activity, learning (appetive and avoidance) and sexual behavior.